Make classes and structures in core/layout fast-allocated.

Source/core/layout/LayoutBox.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2006, 2007 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 418 matching lines @@
     void clearExtraInlineAndBlockOffests();
 
     LayoutSize offsetFromContainer(const LayoutObject*, const LayoutPoint&, bool* offsetDependsOnPoint = nullptr) const override;
 
     LayoutUnit adjustBorderBoxLogicalWidthForBoxSizing(LayoutUnit width) const;
     LayoutUnit adjustBorderBoxLogicalHeightForBoxSizing(LayoutUnit height) const;
     LayoutUnit adjustContentBoxLogicalWidthForBoxSizing(LayoutUnit width) const;
     LayoutUnit adjustContentBoxLogicalHeightForBoxSizing(LayoutUnit height) const;
 
     struct ComputedMarginValues {
+        DISALLOW_ALLOCATION();
         ComputedMarginValues() { }
 
         LayoutUnit m_before;
         LayoutUnit m_after;
         LayoutUnit m_start;
         LayoutUnit m_end;
     };
     struct LogicalExtentComputedValues {
+        STACK_ALLOCATED();
         LogicalExtentComputedValues() { }
 
         LayoutUnit m_extent;
         LayoutUnit m_position;
         ComputedMarginValues m_margins;
     };
     // Resolve auto margins in the chosen direction of the containing block so that objects can be pushed to the start, middle or end
     // of the containing block.
     void computeMarginsForDirection(MarginDirection forDirection, const LayoutBlock* containingBlock, LayoutUnit containerWidth, LayoutUnit childWidth, LayoutUnit& marginStart, LayoutUnit& marginEnd, Length marginStartLength, Length marginStartEnd) const;
 
@@ skipping 473 matching lines @@
         if (UNLIKELY(inlineBoxWrapper() != nullptr))
             deleteLineBoxWrapper();
     }
 
     ensureRareData().m_inlineBoxWrapper = boxWrapper;
 }
 
 } // namespace blink
 
 #endif // LayoutBox_h